WASHINGTON, D.C. (WUSA) - The taxicab companies behind the cabs that didn't pick up a black passenger during a WUSA9 test say the DC Taxi Commission, not them, is responsible for enforcing regulations to carry all passengers.

WUSA9 cameras recorded cabs from Travelers, Riteway, Premium, Dial, Federal, and Lincoln either refusing service directly or driving by our black staffer without stopping.

Only Riteway and Premium cabs returned calls for comment, so Friday, we knocked on doors at the cab headquarters of Dial, Federal, Lincoln, and Travelers.

Cabby managers said most drivers own their own cabs or have rental agreements to operate independently with little control from the cab companies.

Although they acknowledged they could pull the cab's agreement to use the company brand, they said the driver would just repaint his taxi and start work under a different company name.

Repeatedly, the companies pointed their fingers at the DC Taxi Commission as the only way to enforce cab regulations to pick up passengers, regardless of their race or destination.

"We tell all the drivers, you can't discriminate," said Riteway Cab owner Shaw Qureshi, who was one of two cab company managers to respond to our original request. "They know, but they take chances."

The DC Taxi Commission released a statement urging mistreated customers to call a 24-hour service number to handle complaints. You can reach the hotline by calling 855-484-4966 and selecting option one.